. Practical text-book of plant physiology. Plant physiology. PERIODICITY OF GROWTH 295 uniform at all stages of development, or at all parts of the day. An analysis of the curves shows that the rate is slow at first, in- creasing rapidly to a maximum and then decreasing to a minimum, or entire cessation upon the full stature of the organ being reached, the entire action constituting the grand period of growth of the. Fig. 142. Registration, and curves of growth of leaf of Hyacinthus Belgicus, showing daily variations. The upper figure shows actual tracings of pen of precision auxanometer (Fig.
. Practical text-book of plant physiology. Plant physiology. PERIODICITY OF GROWTH 295 uniform at all stages of development, or at all parts of the day. An analysis of the curves shows that the rate is slow at first, in- creasing rapidly to a maximum and then decreasing to a minimum, or entire cessation upon the full stature of the organ being reached, the entire action constituting the grand period of growth of the. Fig. 142. Registration, and curves of growth of leaf of Hyacinthus Belgicus, showing daily variations. The upper figure shows actual tracings of pen of precision auxanometer (Fig. 139). The line E-Fis the record of growth during three nights and two intervening days (63 hours); US, for 88 hours. Lower figure. G-H, curve of growth showing daily variations. The maximum occurs between midnight and 4. A. M., and the minimum about noon, at which time it is nearly zero. A comparison with the thermograph curve, T-M, shows that the minimum growth takes place at the highest temperature, and is indicative that this temperature is above the optimum for the species. XII denotes midnight; 12, noon. organ. If the growth of a stem is followed by actual calibration of the elongating internodes, it will be found that the approaching termination of the period is marked by many irregularities. Among these, it may be mentioned, that variously distributed regions of narrow limits continue a slight increase after the main regions have Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original MacDougal, Daniel Trembly, 1865-1958. New York [etc. ] Longmans, Green, and Co.
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectplantph, bookyear1901
